[Dwarf-Discuss] Possible ambiguity with DW_CFA_remember_state/store_state

Paul Pluzhnikov ppluzhnikov at google.com
Sat Jun 13 09:39:07 PDT 2009

>On Fri, Jun 12, 2009 at 07:46:34PM -0400, John DelSignore wrote: FWIW,
>> TotalView saves the CFA along with the explicitly-numbered registers. So,
>> it seems that TotalView and GDB agree, and that GCC is the outlier. IMHO,
>> it's two against one, so GCC should be fixed.

> If TotalView saves CFA along with explicitly-numbered registers on
> DW_CFA_remember_state and restores CFA state in DW_CFA_restore_state, then
> it matches what GCC expects and what GCC unwinder does, it is GDB that
> wasn't saving/restoring CFA state (and GCC unwinder before 2006-10-26,
> but GCC really started emitting these two unwind ops last month).

That's my understanding of John's message as well.

John, could you run the test case from
under TotalView, and confirm that TV produces correct stack trace for it?

Paul Pluzhnikov

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